Tool for surfacing and forming fibrous material



June 14, 1932. A. B. JOHNSON 1,862,531

TOOL FOR SURFACING AND ORMI&G %IBROUS MATERIAL Filed April 12, 1930 2 Sheets-Sheet 1 i E i I J h w I I I l I June 14, 1932. B JQHNSQN 1,862,681

TOOL FOR SURFAGING AND FORMING FIBROUS MATERIAL ter in the interior of houses.

Patented June 14, 1932 PATENT OFFICE ARTHUR IB. JOHNSON, OF MINNEAPOLIS, MINNESOTA TOOL FOR SURFAOING AND FORMING FIIBROUS MATERIAL Application filed April 12,

My present invention provides a highly efficient tool for shaping and surfacing felted fibrous materials such for example, as the insulating board sold to the trade under the 5 trade name Insulite or the insulating board sold to the trade under the name of Celotex. These insulating materials are made from wood, sugar cane or similar fibrous pulp intertangled and compressed into form of self- 19 sustaining sheets or boards of considerable strength and capable of various uses such, for example, as insulating material in refrigerators and in houses. Such materials are also found of great utility as a substitute for plas- This material is primarily manufactured in large sheets having quite rough surfaces and of quite irregular thickness and in application of such fibrous insulating material to its various uses, there is developed a great demand for smaller sheets in the form of strips or panels of uniform thickness with a smooth outer surface and having special forms such as lapped joints, raised panel efiects and the like. In

the past it has been customary to employ a series of large grinding and sanding drums to dress the material down to a desired thickness and smooth the surface thereof, to trim the material and to cut the same into smaller panels of a desired size by use of circular saws or the like and to bevel the edges thereof when so desired by means of circular saws or knives set to cut at a desired angle. These devices hitherto used have not satisfactorily solved the problem nor made possible the formation of many desirable reductions, bevels, cuts and surfacing of such insulating material.

My invention provides a tool or device which in actual practice has been found to be 0 eflicient to out not only straight bevels and 1930. Serial No. 443,679.

of an inch in width and they are set with their teeth staggered so that the surface cutting action of the teeth of the adjacent saws do not cut simultaneously at the same point. For the cut-ting of fiat surfaces, the teeth of the adjacent saws will have their points ground so that they lie in a common cylinder surface, the axis of which is the axis of rotation of the teeth; but for the cutting of beveled surfaces either straight or rounded the teeth of the adjacent saws will be ground off obliquely transversely of the saw planes to correspond to the bevel or outline that is to be cut on the insulating material. Preferably, at intervals, cut-off saws of larger diameter than the surfacing sa-ws are clamped into or against the surfacing saws so that the insulating material may be simultaneously beveled, grooved, surfaced and cut into strips.

In the accompanying drawings, which illustrate the invention, like characters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is an elevation with some parts in section showing the improved tool designed to surface and bevel the fibrous material while cutting the same into strips;

Fig. 2 is a section taken on the line 22 of Fig. 1;

Fig. 3 is a fragmentary perspective showing portions of the beveling and cutting saws Fig. 4- is an enlarged section taken on the line 4-4 of Fig. 2;

Fig. 5 is a fragmentary perspective showing a portion of one of the strips cut by the tool used as shown in Fig. 1;

Fig. 6 is a fragmentary view showing the staggered arrangement of the two adjacent saws of the tool;

Fig. 7 is a view corresponding to Fig. 6 but s hovying the teeth of the saws given lateral set Fig. 8 is a view corresponding to Fig. 1, but illustrating a tool arranged with saws for beveling and cutting the insulating material, the saws for surfacing the face thereof being omitted;

Fig. 9 is an end elevation of one of the strips cut by the tool used as in Fig. 8, some parts being broken away;

Fig. 10 is a fragmentary view in vertical section illustrating the action of the tool shown in Fig. 8;

Fig. 11 is a view corresponding to Fig. 1, the outline of the saws forming the tool being indicated diagrammatically but illustrating the line on which they will be ground to form raised panels having rounded portions;

Fig. 12 is a fragmentary section of the tool shown in Fig. 11, the saws being here indicated;

Fig. 13 is an end elevation of one of the panels cut by the tool used as shown in Figs. 11 and 12, some parts being broken away; and

Fig. 14 is a modification showing the saws arranged and applied to form a molding from fibrous insulating material.

Referring first to the construction illustrated in Figs. 1 to 41;, inclusive, the numeral 15 indicates a. mandrel or shaft on which the saws are mounted, the same being clamped together 011 the mandrel by clamping nuts 16 and washer-like clamping collars 17. The large diameter cut-off saws are indicated by the numeral 18; the saws for cutting a flat surface on the face of the insulating material are indicated by the numeral 19 and the saws for cutting bevels on the edges of the strips of insulatng material are indicated by the numeral 20. As best shown in Fig. at, the points of the teeth of the saws 19 are grounded on a cylindrical surface while the points of the teeth of the saws 20 are ground in a conical surface so that they produce straight bevels. The form of strips A cut by the teeth, F 1, is shown in Fig. 5. Very wide sheets of insulating material may be simultaneously cut into any desired number of strips, the strips beveled, the strips dressed down to a desired thickness, and their surfaces smoothed off by one operation. In Figs. 1 and 4, the ragged outside edge portions of the sheet from which the strips are cut oil are indicated at a.

The insulating strips cut by the teeth, shown-in Figs. 8 and 10, are adapted to be tied together to form beveled raised panels with lapped joints but with the unbeveled faces of the panels left in natural condition; and hence this tool comprises only the shaft or mandrel 15, cut-ofi' saws 18, and bevel cutting saws 20, the said saws being clamped together in groups and onto the mandrel by clamping nuts 16*, washer-like clamping collars 16", and nut-acting clamping collars 17 The panel or strip cut in Figs. 8, 9 and 10 is designated by the letter B.

In the arrangement shown in Figs. 11 and 12, the cut-off saws are indicated at 18*, the cylindrically ground surfacing saws at 19 and the eoncavely ground beveling saws at 20. The form of panel cut as illustrated in Figs. 11 and 12 is marked C.

In the arrangement shown in Fig. 14 for cutting a molding out of insulating material,

- or rounded surfaces 19 that conform to the arc of a circle struck from the axis of the saws. In practice I have found that saws having their ends ground down in this manner make a smoother surface on fibrous material than can be produced by sharp pointed saws. The teeth of sharp pointed saws have some tendency to raise the fibers of the material therebehind, leaving a fuzzy appearing surface while the blunted saw teeth out the surface of the material with their leading edges and then rub the surface of the material with their rounded blunt portions, thus preventing the fibers from raising and producing a kind of polished appearance on the surface of the material.

In practice I have found that the front ends 19 of the saw teeth 19 should, for best results, extend circumferentially of the saws a dis tanee approximately equal to the width of the saw teeth. These approximate proportions of length and width of the blunt ends 19 of the saw teeth are clearly shown, especially in F ig. 3 of the drawings.

What I claim is:

A tool for surfacing fibrous materials comprising a plurality of toothed disk saws closely clamped together, the teeth of the several saws having blunt ends that conform I to the periphery of a circle struck from the axis of the saws and said blunt ends extending circumferentially of the saws a distance substantially equal to the Width of the saw teeth.

In testimony whereof I afiix my signature.

ARTHUR B. JOHNSON. 

